Michael J. May's place is where old houses go to live.

Mellow gold antique bead-board from a long-gone old house tiles the kitchen ceiling in his 1870 Federal-style house. A Prairie-style casement window, redeemed from a Waterford, Wis., house, is now a mullioned glass door on a kitchen cabinet. The side door is carved cedar, crafted with Old World precision and still inset with the original German scrolled and frosted glass. He pulled it, intact, from a garbage bin.

Until recently, it was mainly the environmentally correct and very thrifty used architectural elements salvaged from historic buildings about to be torn down.

Now, historic house parts are reclaiming the limelight that once made them glow, and they are being used as grace notes and focal points in brand-new houses and whole-house renovations of old buildings.

Designers and contractors who specialize in salvage are in demand as homeowners struggle to reconcile their inspiration with the nitty-gritty of fitting old things into new spaces. Meanwhile, the same excitement that is landing salvage front and center in a rush of books and magazines is also making it much tougher to find old materials.

Interest in salvage has been steadily growing for about five years, but "just within the last two years, builders are starting to look for stuff," said Ken Melchert.

He and wife Rebecca own the Harp Gallery, an antique and salvage store in Appleton, Wis., where tall French doors cluster around $1,800 oak fireplace mantels.

Brian Coleman, a Seattle psychologist, salvage guru and author of "Extraordinary Interiors: Decorating with Architectural Salvage and Antiques" (Gibbs Smith, 2005, $39.95) says that the rising interest in historic interiors has intrigued people who own houses of all ages with the possibilities of salvage.

"You can, certainly, find things cheaper that are salvaged, but that's not the only point. The point is to be creative, and use your imagination," he said.

One project from his book: a turn-of-the-century barbershop interior installed, nearly whole, as a master bath. The framed-in space and roughed-in plumbing were adjusted to accommodate the marble walls and commercial sinks.

"It's not perfect, but that's part of the fun, to see how you can use it," said Coleman.

People come upon a sparkling stained-glass window or long, narrow, carved cabinet door and love it, and then aren't sure what to do next.

"A real common comment I hear is, 'I saw a stained-glass window I really liked, but I didn't buy it because it didn't fit,' " said Coleman. "I tell them, 'go buy it.' What you do is, you add a little around the edges, or take a little away. It's easy" to retrofit.

Easy if you know what you're doing, that is. Many homeowners and contractors have a working knowledge only of mass-produced, standardized building materials and measurements. Antique doors, windows and fixtures that might have been custom-built for the original space require a lot of reverse engineering to fit into a new space.

May, who runs M.J. May Building Restoration, said he's getting more and more calls from potential clients who want his help in sizing up a piece -- literally and figuratively.

Clients come across a built-in bookcase or unusual window and need some expert help to figure out if it can be retrofitted into an existing room, or want to learn if May agrees that the piece is just the thing for a renovation or addition they've long been considering.

"It's a big design challenge to make an old mantel not just look like it was plopped in. You have to match the scale with the scale of the room" and other elements, like doors, said Allyson Nemec, principal of Milwaukee's Quorum Architects, which specializes in historic building renovation.

She and other salvage-savvy designers and contractors agree that building with salvage involves adjustments all the way along in the design, clients' expectations, and the materials.

The best way to start is with a strong sense of how the finished space will look and what key architectural elements will anchor it.

With sketches in hand, homeowners often take years collecting salvaged parts that might be perfect -- or might end up being someone else's lucky find.

With materials at the ready, the project can begin. Then the real fun begins.

Contractors sometimes find that old pieces have to be minutely adjusted to comply with building codes and the homeowners' evolving sensibilities. And everybody has to have lots of patience as the old materials and new house fit around each other.

Tim and Kathleen Steep bought their Victorian farmhouse with the aim of renovating it using as much salvage as they could. Tim, who runs his own firm, Tim's Carpentry and Remodeling Inc., considered it a course in advanced salvage techniques so that he could better serve his growing base of customers who want to use salvage.

The kitchen was already designed when the couple found a set of maple wall cabinets at Milwaukee's Salvage Heaven. Never painted, the 46-inch-tall cabinets perfectly matched base cabinets that the Steeps discovered in a neighbor's garage.

After completely changing the design around the bank of cabinets, Steep replaced the cabinets' wood fronts with glass and showcased them between two windows.

In a second-floor loft, he is making a balcony railing from an 11-foot stretch of Gothic-arched kneeling bench from a church. "You have to have your plan, but when you find something old you like, you have to change the plan," he said.

Not everybody catches on. Jonathan and Beth Park bought a Victorian duplex in Milwaukee knowing that they'd have to gut it down to the studs and rebuild it.

At first, they hoped to save and reuse the trim from the 1892 Queen Anne. But when they learned the wood was covered in lead-based paint, they decided to replace it all with salvage.

Jonathan put the word out that he was looking for miles of trim, and ended up buying the interior of one house and half of another. He ended up with 30 doors and 1,200 linear feet of molding -- but it was all from an early Arts and Crafts style house built in 1904.

"It's distinctly different" in style and proportion from the doors he had to throw away, said Jonathan.

While his contractor grudgingly adjusted the plans to accommodate the shorter, wider doors, the Park crew meticulously extracted the doors, frames and hardware together, as pre-hung working units, so they could be easily slid into the new openings.

The contractor didn't get the memo. When it was time to move the door units into place, "he had his guys break down the door jambs and we had to fit them all together again. The guys took off all the door hardware and the bag of knobs was buried under a pile of wood. I eventually found them after I bought some more," said Jonathan.

Salvage dealers and specialty contractors say that this kind of thing happens all the time.

"By the time people get to me, they've heard 'no' from six or seven contractors," said May. Many contractors, he said, "don't like to color outside the lines."

Non-standard parts add time and hassle to construction projects at every step, especially if they have to be fitted into contemporary plumbing and electrical systems, said Mike Litchfield, author of "Renovation," a nuts-and-bolts reference.

Intermediate pieces to join old fittings with new systems can be "tricky to find," he says. Even for simple retrofits, the antique parts have to be trimmed or built out to make them at home.

After all that work, homeowners sometimes feel they might want to take some of that good old stuff with them if they sell the house.

Usually, what's nailed to a house is sold with the house, so the solution is a semi-permanent or free-standing installation. Some people hang old stained-glass windows from the frame instead of installing them in the frame, or position pillars as accents instead of structural elements.

The showcase in May's dining room is an oak Arts & Crafts buffet with leaded-glass doors accented with medieval crests.

It was the sturdy sideboard used by four generations of the same Burlington family before the house it was in was torn down to make way for a parking lot.

"If I found a true match for the house, something that was more period, more accurate, I'd exchange it," he said.

Michael J. May has salvaged Roman columns, Italianate corbel, an Art & Craft book case and other items for his home in Burlington, Wis.